A quite significant number of monoclonal antibodies is under investigation and needs to be studied in experimental animals, before entry into human can be considered for the first trial purposes. Important criteria like bio-availability and antibody clearance just to mention two of them have to be studied. Many of these studies require the quantification of the antibody in the background of the experimental animal's own antibodies. In most cases mammals are used as experimental animals. Toxicology often is first assessed in rodents like mice or rats.
Mammals usually have between about 10 to about 30 milligram of antibody per ml in the circulation. Monoclonal antibodies typically have to be tested with serum levels ranging from about between 1 nanogram per ml to about 100 microgram per ml. The antibody in question, thus, has to be detected against a background of experimental animal's antibodies which are in an excess of about 100-fold to 10 million-fold.
The detection of an antibody derived from a different species than the experimental animal in the background of an experimental animal's antibody represents quite a significant task to the pharmacologist.
In WO 2008/031532 an anti-drug antibody assay is reported. The detection of a therapeutic antibody in an experimental animal is reported in WO 2006/066912. In U.S. Pat. No. 5,332,665 species specific, high affinity monoclonal antibodies are reported. Non-cross reactive anti-IgG antibodies are reported in WO 2011/048043.